The present invention relates to tracked vehicles and, more particularly, to an assembly to adjust the track tension of the tracked vehicle.
Generally, a tracked vehicle includes a frame, a first sprocket supported by the frame, a second sprocket supported by the frame in spaced relation to the first sprocket, the first sprocket and the second sprocket being rotatable about a first axis and a second axis, respectively, and an endless track extending about the first sprocket and the second sprocket. One of the first sprocket and the second sprocket, for example, the first sprocket, is movable relative to the frame in a direction perpendicular to the first axis to adjust the tension of the track.
The vehicle also includes a tension adjustment assembly to adjust the track tension. A typical adjustment assembly includes a cylinder assembly connected to the movable sprocket and operable to move the sprocket to adjust the track tension. The cylinder assembly includes a movable member connected to the movable sprocket and movable along a movable member axis generally perpendicular to the movable sprocket axis, and a rotatable member connected to the movable member and rotatable about the movable member axis to cause movement of the movable member along the movable member axis.
The rotatable member includes an operating end which is engaged by an operator with an adjustment tool, such as a wrench. When the rotatable member is rotated, the movable member moves along the movable member axis to move the movable sprocket and to thereby adjust the tension of the track.
One problem with the above-described adjustment assembly is that the operating end of the rotatable member is located inwardly of the outer edge of the track and/or of the frame. As a result, the operating end is difficult to reach and engage with the adjustment tool.
Another problem with the above-described adjustment assembly is that adjustment tool is rotated in a plane which is generally perpendicular to the movable member axis and to the plane defined by the outer surface of the track and/or of the frame. Due to the restrictions of the track and/or of the frame, the adjustment tool can only rotate in narrow arc to adjust the rotatable member and must be continuously disengaged and repositioned to adjust the track tension.
The present invention substantially alleviates the problems with the above-described adjustment assembly and tracked vehicle. In particular, the adjustment assembly of the present invention includes a rotatable shaft located outwardly from the operating end of the rotatable member and a coupling connected between the shaft and the rotatable member for rotating the rotating member in response to rotation of the shaft. Preferably, the shaft is transverse to the rotating member, and the coupling transmits rotation xe2x80x9caround a corner.xe2x80x9d The operating end of the shaft is more easily engageable by the adjustment tool. Also, because the adjustment tool rotates in a plane generally parallel to the plane defined by the outer surface of the track and/or of the frame, the adjustment tool can rotate in a greater arc without being interfered with by the track and/or by the frame.
More particularly, the present invention provides a track tension adjustment assembly including a tension adjustment mechanism connected to a movable sprocket, a shaft supported for rotation about a shaft axis extending at an outward angle from and, preferably, generally transverse to the rotatable member axis and a coupling connected between the shaft and the rotatable member to translate rotation of said shaft into rotation of the rotatable member to thereby move the movable sprocket and adjust the tension of the track. The adjustment assembly also preferably includes a keeper assembly selectively engageable with the shaft to prevent rotation of the shaft and to prevent adjustment of the track tension.
In addition, the present invention provides a tracked vehicle including a frame, first and second sprockets, a track extending about the sprockets, and a tension adjustment assembly. One of the sprockets is movable relative to the frame to adjust the tension of the track. The tension adjustment assembly includes a tension adjustment mechanism connected to the movable sprocket, a shaft supported for rotation about a shaft axis extending generally transverse to the rotatable member axis and a coupling connected between the shaft and the rotatable member to translate rotation of said shaft into rotation of the rotatable member to thereby move the movable sprocket and adjust the tension of the track.
Other features and advantages of the invention will become apparent to those skilled in the art upon review of the following detailed description, claims and drawings.